BY R. VON LENDENFELD, PH.D. 341 



IV. FAMILY APLYSINID^E. 



Ceraospongise with a skeleton composed of anastomosing fibres 

 which consist of a thick core and a thin horny wall. Ground 

 substance filled with granules, intransparent. Ciliated chambers 

 small and pear-shaped. 



1. SUB-FAMILY APLYSININ.E. 



Aplysinida? without Flesh-spicules. 



2- SUB-FAMILY APLYSISSIN^. 

 Aplysinidae with Flesh-spicules. 



V. FAMILY HIRCINTD^E. 



Ceraospongiae with a skeleton composed of anastomosing horny 

 fibres with a narrow axial canal. The ground substance filled 

 with granules. Besides there are dense masses of long and thin 

 thread-shaped fibrilles with a knob at each end. 



1. SUB-FAMILY HIRCININ.E. 

 Hircinida? without Flesh-spicules. 



2. SUB-FAMILY 7 HIRCISSNLE, 

 Hercinidre with Flesh-spicules. 



IV. ORDO MONACTICEILE. 



8PONGLE WITH A SKELETON COMPOSED OF ANASTOMOSING 

 HORNY FIBRES, WITHIN WHICH THERE ARE MONOAXIAL 

 SPICULES. SOMETIMES WITH FLESH-SPICULES. 



1. FAMILY CHALARCHIM:. 



Monacticera with anastomosing horn fibres in the axea of which 

 there are longitudinal minute biacerate spicules. 



